Injection drug use is a common mode of HIV transmission. Methadone can reduce injection heroin use and injection-related HIV risk behaviors, but most injection heroin users are difficult to engage in treatment. A randomized study is planned over 5 years to evaluate the effectiveness of the Therapeutic Workplace in promoting engagement in methadone treatment and increasing drug abstinence in unemployed, out-of- treatment, injection heroin users. The Therapeutic Workplace is a novel employment-based intervention that uses wages for work to reinforce clinically important behavior change. Workplace participants are paid to work in a supported workplace. To promote clinically important behaviors, wages are arranged contingent both on work and those behaviors. In this study, participants will be invited to attend the workplace and enroll in methadone treatment. During a workplace induction period, participants will be allowed to work and earn wages independent of whether they enroll in methadone treatment and independent of their drug use. After 4 weeks, workplace participants (N = 162) will be randomly assigned to one of three groups. All groups will be invited to attend the workplace for 26 weeks. "Methadone Contingency" participants will be required to take methadone to work, and will receive a brief pay decrease for missing a dose. Because many heroin users also use cocaine, even during methadone treatment, "Methadone and Abstinence Contingency" participants will be required to take methadone to work, and will receive a brief pay decrease for missing a methadone dose or for providing a cocaine-positive urine sample. "Usual Care" participants will be allowed to work independent of their methadone use or urinalysis results. We expect that the "Methadone Contingency" group will increase methadone adherence and decrease heroin use;and that the "Methadone and Abstinence Contingency" group will increase methadone adherence, and decrease heroin and cocaine use. Since methadone is effective at retaining patients in treatment once enrolled, we expect that once the "Methadone Contingency" engages participants in methadone treatment, the methadone will serve to maintain their participation in treatment after exposure to the Therapeutic Workplace ends. The Therapeutic Workplace could serve as a bridge to engage out-of-treatment injection heroin users into methadone treatment, and to reduce their drug use and injection-related HIV risk behaviors.